This invention relates generally to weight measuring devices, and more particularly to a portable and foldable compact weight measuring device utilizing an arrangement of sealed fluid containing bladders.
In our extremely weight conscious society, the need to know one's weight on a weekly, daily and sometimes hourly basis has become and obsession. Almost all who are on a diet of one form or another have an accurate weight scale in their residence. Additionally, offices, banks and many supermarkets also provide public access to weight scales so that individuals can easily monitor progress (or failure) at loosing or controlling body weight.
However, when one travels, the intermediate and final destinations many times do not have an accessible weight scale available. Virtually all of the presently available weight scales for home and office use are far too cumbersome to be carried along with other baggage and therefore the nervous tension which develops from not knowing one's body weight fluctuations heightens during the trip away from access to these weight scales - many times igniting nervous appetites.
The above is only one example of the need for a portable, compactible light weight scale for weighing objects.
Prior art discloses U.S. Pat. No. 4,537,266 teaching a portable compactible scale invented by Greenberg. This device includes a finger-like compactible bladder containing non-compressible fluid. The device itself is made compactible by rolling it into a cylindrical shape from its flat in-use configuration.
A weight and pressuring measuring device invented by Burkhardt as set forth in U.S. Pat. No. 4,909,339 teaches a water and pressure measuring device having a fluid filled cushion pad connected to a pressure indicator. The device, which measures pressure produced by a weight load applied thereatop also includes a thin stepping pad which may be rolled up or outstretched above the cushion pad to increase the solidity of the support for the object to be weighed.
U.S. Pat. No. 4,431,072 discloses a weighing device invented by Stepp for determining the axle load weight of a vehicle and includes a platform with tire guide rails and inflatable air bags. An air pressure gauge connected to the air bags is provided to measure the vehicle axle weight.
Another device for measuring the axle weight of vehicles such as trucks and the like is disclosed in U.S. Pat. No. 3,698,492 invented by Lejuene. This device is a hydraulic balance having two deformable parallel tubes each containing a fluid under pressure each of which is measured separately.
Three other weight measuring devices are known to applicant, the first being a weight apparatus disclosed in U.S. Pat. No. 1,936,178 invented by Sykes, a second disclosed in U.S. Pat. No. 2,857,152 invented by Aske and a third, a hydraulic bellow-type scale invented by Chen disclosed in U.S. Pat. No. 4,366,876. These devices are quite dissimilar to that of the present invention.
The present invention provides a portable, easily transportable weight scale particularly useful for individuals while traveling, but also useful in any situation where a relatively light duty, thin, transportable weight scale is required. The device includes a plurality of flat fluid filled bladders arranged side by side and interconnected by fluid carrying tubular conduits. Rigid upper and lower plates positioned against the upper and lower surfaces of each bladder define parallel spaced working and ground engaging surfaces, respectively, which serve to pressurize the bladder arrangement when a load is applied so that a pressuring sensing and converting unit may produce an electrical signal to a digital readout for determining the weight of the object atop the bladder arrangement. The device is easily foldable for convenient transporting and may be provided in a broad range of sizes and configurations, depending upon the application.